The effects of n-decanol, n-hexadecanol, n-octyl(oxyethylene)3 alcohol and cholesterol on gramicidin single-channel lifetime in planar lipid bilayers have been determined. The bilayers used were formed from a solution of monoolein in squalene. Measurements have also been made of the above compounds' effects on membrane thickness (as measured by electrical… (More)

—We present a comparison between data acquired with frequency-modulated ground-penetrating radar (GPR) and satellite synthetic aperture radar (SAR). Both radars are polarimetric and operate at a center frequency of 5.3 GHz. The field site is the polythermal glacier Kongsvegen, Svalbard. Along glacier GPR profiles cover the ablation area and the accumulation… (More)

—The question of penetration of synthetic aperture radar (SAR) signals at C-band frequency into polar glaciers is addressed by comparing ground penetrating radar (GPR) and SAR backscatter signatures. Profiles of the Kongsvegen glacier, Svalbard, were obtained with a C-band GPR. The received signal is converted to the equivalent radar cross section using the… (More)

The lipids extracted from the membrane of the thermophilic archaeobacterium Sulfolobus solfataricus have an unusual bipolar structure. Each molecule is formed by two isoprenoid chains (with up to four cyclopentane groups per chain) ether-linked at both ends to glycerol or nonitol groups. These groups can be variably substituted, mainly with complex sugars.… (More)

—We use ground-penetrating radars (GPRs), firn cores, and electromagnetic finite-difference time-domain (FDTD) numerical modeling to characterize the GPR response to a frozen high-arctic firn pack. As a result of extensive summertime perco-lation, the firn pack comprises a high fraction of ice layers, lenses, and vertical glands. We show that the GPR… (More)